Renal disease is a significant health challenge in the United States and elsewhere. Lack of organ transplant availability means that most patients are treated by dialysis, with roughly ten times as many patients receiving hemodialysis versus other forms. To minimize treatment time, hemodialysis requires a relatively large blood volume flow rate typically achieved through an arteriovenous shunt created through surgery. This shunt creates a low resistance pathway that can result in significantly increased flow rate through an arteriovenous fistula. Grafts have also been widely used.
In recent years, arteriovenus fistulas have been increasingly used to the exclusion of grafts, as data has emerged demonstrating that fistulas tend to have better long term patency rates and reduced requirements for intervention. There are nevertheless various challenges associated with fistula usage. After surgical creation of an arteriovenous fistula, the inflow and outflow vessels must dilate sufficiently and the venous tissue must generally undergo a remodeling process known as fistula maturation in order to be able to sustain the high flow rates needed for dialysis. This maturation process is only successful in about sixty percent of arteriovenous fistulas.
Another common problem is tissue proliferation along the lumen of the vein know as neointimal hyperplasia or NIH. NIH may lead to stenosis, reduced flow and ultimately failure of the fistula. Abnormal flow through an arteriovenous fistula is often observed with auscultation in the nature of characteristic vibration, believed likely to stem from turbulent flow through the vasculature. Various devices and techniques for use in fistula formation have been proposed over the years. Such technologies, however, suffer from a variety of drawbacks and shortcomings as evidenced by the still relatively low success rates of fistula maturation. Moreover, some devices for fistula formation are purpose-engineered for certain specific applications and may be less well suited to others. U.S. Pat. No. 8,523,800 to Brenneman et al., contemplating a shunt rivet for implantation in the aorta and inferior vena cava, is one such example.